U.S. patent application number 12/788000 was filed with the patent office on 2010-12-02 for high-heat-retention ladle for carrying molten aluminum.
Invention is credited to Sock Hwan Choi, Young Myung Hong, Eok Soo Kim, Kyung Mook Lim, Jin Young Park.
Application Number | 20100301073 12/788000 |
Document ID | / |
Family ID | 43219091 |
Filed Date | 2010-12-02 |
United States Patent
Application |
20100301073 |
Kind Code |
A1 |
Kim; Eok Soo ; et
al. |
December 2, 2010 |
HIGH-HEAT-RETENTION LADLE FOR CARRYING MOLTEN ALUMINUM
Abstract
A high-heat-retention ladle for carrying molten aluminum
includes a ladle body defining therein a storage space, which
contains molten aluminum therein, the ladle body including a molten
metal inlet and a molten metal outlet, which allow the storage
space to communicate with outside, a cover opening and closing the
inlet of the ladle body, and a stopper opening and closing the
outlet of the ladle body. Each of the ladle body and the cover has
an outer shell, which defines a contour thereof, and a multi-layer
insulation structure inside the outer shell. The multi-layer
insulation structure includes two or more refractory layers. The
molten aluminum contained inside the storage space has a
temperature drop rate of 5.degree. C./min or less. It is possible
to carry the molten aluminum for a long time in a heat-insulated
state and cast a product by directly pouring the molten aluminum
into a mold.
Inventors: |
Kim; Eok Soo; (Ulsan,
KR) ; Hong; Young Myung; (Ulsan, KR) ; Lim;
Kyung Mook; (Seoul, KR) ; Choi; Sock Hwan;
(Ulsan, KR) ; Park; Jin Young; (Ulsan,
KR) |
Correspondence
Address: |
CHRISTIE, PARKER & HALE, LLP
PO BOX 7068
PASADENA
CA
91109-7068
US
|
Family ID: |
43219091 |
Appl. No.: |
12/788000 |
Filed: |
May 26, 2010 |
Current U.S.
Class: |
222/597 |
Current CPC
Class: |
B22D 41/00 20130101;
B22D 41/14 20130101 |
Class at
Publication: |
222/597 |
International
Class: |
B22D 41/14 20060101
B22D041/14; B22D 41/00 20060101 B22D041/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 27, 2009 |
KR |
10-2009-0046335 |
Claims
1. A high-heat-retention ladle for carrying molten aluminum,
comprising: a ladle body defining therein a storage space, which
contains molten aluminum therein, wherein the ladle body includes a
molten metal inlet and a molten metal outlet, which allow the
storage space to communicate with outside; a cover opening and
closing the inlet of the ladle body; and a stopper opening and
closing the outlet of the ladle body, wherein each of the ladle
body and the cover has an outer shell, which defines a contour
thereof, and a multi-layer insulation structure inside the outer
shell, the multi-layer insulation structure including two or more
refractory layers, whereby the molten aluminum contained inside the
storage space has a temperature drop rate of 5.degree. C./min or
less.
2. The high-heat-retention ladle according to claim 1, wherein the
multi-layer insulation structure of the ladle body includes an
outer molded refractory, an outer castable refractory, an inner
molded refractory, and an inner castable refractory, which are
stacked sequentially over an inner surface of the outer shell
toward inside of the ladle body, wherein the inner castable
refractory is made of a material chemically unreactive with
aluminum, and the inner molded refractory is made of a silicon
dioxide based molded material that alleviates weight and impact
between the inner castable refractory and the outer castable
refractory.
3. The high-heat-retention ladle according to claim 2, wherein the
inner castable refractory includes an inside wall protruding upward
from a bottom central portion of the ladle body.
4. The high-heat-retention ladle according to claim 1, wherein the
multi-layer insulation structure of the ladle body comprises a
castable refractory structure provided innermost of the ladle body,
the castable refractory structure being unreactive with the molten
aluminum, wherein the castable refractory structure includes: an HD
board type castable refractory provided on a side wall of the ladle
body; a castable refractory provided on a side wall in the outlet
side, the castable refractory including silicon dioxide
(SiO.sub.2), aluminum oxide (Al.sub.2O.sub.3), and calcium oxide
(CaO); and a castable refractory provided on a bottom of the ladle
body, the castable refractory made of silicon nitride
(Si.sub.3N.sub.4) coupled silicon carbide (SiC).
5. The high-heat-retention ladle according to claim 4, wherein the
castable refractory structure further includes an outer molded
refractory in contact with an inner surface of the outer shell of
the ladle body, wherein the outer molded refractory comprises a
microporous insulator, which includes silicon dioxide (SiO.sub.2)
and silicon carbide (SiC).
6. The high-heat-retention ladle according to claim 5, wherein the
castable refractory structure further includes an inner molded
refractory interposed between the castable refractories and the
outer molded refractory, wherein the inner molded refractory
comprises ceramic pelts to which inorganic binder is impregnated.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority from Korean Patent
Application Number 10-2009-0046335 filed on May 27, 2009, the
entire contents of which application is incorporated herein for all
purposes by this reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a high-heat-retention ladle
for carrying molten aluminum, and more particularly, to a
high-heat-retention ladle that can carry molten aluminum for a long
time in a heat-insulated state in order to cast a product by
directly pouring the molten aluminum into a mold without having to
convert raw materials into an ingot and then melt the ingot
again.
[0004] 2. Description of Related Art
[0005] Aluminum is used as a component material for a variety of
machines such as vehicles and aircraft. Aluminum is generally used
in the form of alloys combined with other light metals in order to
increase its strength, and aluminum alloys can reduce the weight of
products by 50% or more compared to typical steel materials.
Therefore, the use of aluminum materials is continuously increasing
due to their advantageous effects. For example, aluminum materials
can improve performance by decreasing the weight of structures, and
can especially reduce the use of energy and the output of
pollutants in consideration of high oil prices and environmental
problems, which are becoming more important these days.
[0006] A considerable portion (about 40%) of aluminum (alloy)
products is produced by a casting method in which raw materials are
melted by loading them into a smelter, and then molten metal is
formed into a particular shape by pouring it into a mold. The
casting method is widely used in the manufacture of components of
machines since it has excellent advantages in terms of productivity
and size consistency.
[0007] A conventional process of producing products by aluminum
casting such as die casting includes first processing of making an
aluminum ingot by melting raw materials and second processing of
casting final products by melting the aluminum ingot again.
[0008] That is, an aluminum ingot is prepared as an intermediate
product by melting an aluminum raw material, which is refined or
reproduced in a raw material alloying plant, alloying metals, and
the like and pouring molten metal into a mold. Afterwards, a
product casting plant produces a final product by again melting the
aluminum ingot, which is supplied thereto, and performing a casting
process, such as die casting.
[0009] As described above, in the conventional art, aluminum is
carried in the form of an ingot to the casting plant even though it
is melted in the raw material alloying plant. Therefore, the
casting process of making the aluminum ingot in the alloying plant
incurs high manpower and facilities costs, and the cycle of
supplying aluminum is prolonged, thereby decreasing cost efficiency
and productivity.
[0010] The product casting plant also incurs a great amount of time
and expense in the process of melting the aluminum ingot again,
thereby decreasing cost efficiency and productivity. In addition, a
considerable amount of materials is additionally lost due to the
oxidation of aluminum during melting. Furthermore, this causes
problems of a deteriorated working environment and air pollution in
the surroundings since a great amount of dust and pollutants, such
as SOx or NOx, is produced.
[0011] The information disclosed in this Background of the
Invention section is only for the enhancement of understanding of
the background of the invention, and should not be taken as an
acknowledgment or any form of suggestion that this information
forms a prior art that would already be known to a person skilled
in the art.
BRIEF SUMMARY OF THE INVENTION
[0012] Various aspects of the present invention provide a
high-heat-retention ladle that can carry molten aluminum for a long
time in a heat-insulated state in order to cast a product by
directly pouring the molten aluminum into a mold without having to
convert raw materials into an ingot and then melt the ingot
again.
[0013] In an aspect of the present invention, the
high-heat-retention ladle for carrying molten aluminum may include
a ladle body defining therein a storage space, which contains
molten aluminum therein, the ladle body including a molten metal
inlet and a molten metal outlet, which allow the storage space to
communicate with outside; a cover opening and closing the inlet of
the ladle body; and a stopper opening and closing the outlet of the
ladle body. Each of the ladle body and the cover has an outer
shell, which defines a contour thereof, and a multi-layer
insulation structure inside the outer shell. The multi-layer
insulation structure includes two or more refractory layers. The
molten aluminum contained inside the storage space has a
temperature drop rate of 5.degree. C./min or less.
[0014] According to an exemplary embodiment of the present
invention, the multi-layer insulation structure of the ladle body
can include an outer molded refractory, an outer castable
refractory, an inner molded refractory, and an inner castable
refractory, which are stacked sequentially over the inner surface
of the outer shell toward the inside of the ladle body. The inner
castable refractory can be made of a material chemically unreactive
with aluminum, and the inner molded refractory can be made of a
silicon dioxide based molded material that alleviates weight and
impact between the inner castable refractory and the outer castable
refractory.
[0015] According to an exemplary embodiment of the present
invention, the inner castable refractory can include an inside wall
protruding upward from the bottom central portion of the ladle
body.
[0016] Alternatively, the multi-layer insulation structure of the
ladle body can have a castable refractory structure provided
innermost of the ladle body, the castable refractory structure
being unreactive with the molten aluminum. The castable refractory
structure can includes an HD board type castable refractory
provided on the side wall of the ladle body; a castable refractory
provided on the side wall in the outlet side, the castable
refractory including silicon dioxide (SiO.sub.2), aluminum oxide
(Al.sub.2O.sub.3), and calcium oxide (CaO); and a castable
refractory provided on the bottom of the ladle body, the castable
refractory made of silicon nitride (Si.sub.3N.sub.4) coupled
silicon carbide (SiC).
[0017] Here, the castable refractory structure can also include an
outer molded refractory in contact with the inner surface of the
outer shell of the ladle body. The outer molded refractory can be a
microporous insulator, which includes silicon dioxide (SiO.sub.2)
and silicon carbide (SiC).
[0018] In addition, the castable refractory structure can also
include an inner molded refractory interposed between the castable
refractories and the outer molded refractory. The inner molded
refractory can be ceramic pelts to which inorganic binder is
impregnated.
[0019] According to exemplary embodiments of the present invention
as set forth above, the following effects are realized.
[0020] (1) Since the insulator having a multi-layer structure, in
which the outer molded refractory, the outer castable refractory,
the inner molded refractory, and the inner castable refractory are
stacked sequentially, is provided inside the outer shell to prevent
the heat of molten aluminum from escaping to the outside, it is not
necessary to produce an ingot in a raw material supplying plant to
carry aluminum or melt the ingot again in a product casting plant.
Accordingly, it is possible to reduce manpower and costs, improve
productivity, reduce materials costs, and reduce the output of
pollutants.
[0021] (2) Since suitable types of refractory layers, each of which
has a suitable thickness, are provided to satisfy a variety of
insulating conditions according to the respective portions of the
ladle body, it is possible to reduce the weight of the ladle and
thus improve delivery performance.
[0022] The methods and apparatuses of the present invention have
other features and advantages which will be apparent from, or are
set forth in greater detail in the accompanying drawings, which are
incorporated herein, and in the following Detailed Description of
the Invention, which together serve to explain certain principles
of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is an elevational view showing the outline of a
high-heat-retention ladle for carrying molten aluminum according to
an exemplary embodiment of the invention;
[0024] FIG. 2 is a front elevational cross-sectional view showing
the ladle shown in FIG. 1;
[0025] FIG. 3 is a top plan cross-sectional view taken along the
line A-A' in FIG. 2;
[0026] FIG. 4 is a top plan cross-sectional view taken along the
line B-B' in FIG. 2;
[0027] FIG. 5 is a side elevational cross-sectional view showing
the ladle shown in FIG. 1;
[0028] FIG. 6 is a front elevational cross-sectional view showing a
high-heat-retention ladle for carrying molten aluminum according to
another exemplary embodiment of the invention;
[0029] FIG. 7 is a top plan cross-sectional view of the ladle shown
in FIG. 6; and
[0030] FIG. 8 is a detailed view of a stopper of the ladle shown in
FIG. 6.
DETAILED DESCRIPTION OF THE INVENTION
[0031] Reference will now be made in detail to various embodiments
of the present invention(s), examples of which are illustrated in
the accompanying drawings and described below. While the
invention(s) will be described in conjunction with exemplary
embodiments, it will be understood that the present description is
not intended to limit the invention(s) to those exemplary
embodiments. On the contrary, the invention(s) is/are intended to
cover not only the exemplary embodiments, but also various
alternatives, modifications, equivalents and other embodiments that
may be included within the spirit and scope of the invention as
defined by the appended claims.
[0032] FIG. 1 is an elevational view showing the outline of a
high-heat-retention ladle for carrying molten aluminum according to
an exemplary embodiment of the invention, FIG. 2 is a front
elevational cross-sectional view showing the ladle shown in FIG. 1,
FIG. 3 is a top plan cross-sectional view taken along the line A-A'
in FIG. 2, FIG. 4 is a top plan cross-sectional view taken along
the line B-B' in FIG. 2, and FIG. 5 is a side elevational
cross-sectional view showing the ladle shown in FIG. 1.
[0033] As shown in FIGS. 1 to 5, the high-heat-retention ladle
includes a ladle body 110, a cover 140, and a stopper 180. The
ladle body 110 defines therein a storage space 111, which contains
molten aluminum therein, and has a molten metal inlet 112 and a
molten metal outlet 113 in upper and side portions thereof, which
communicate with the storage space 111. The cover 140 is coupled to
the upper portion of the ladle body 110 to open and close the inlet
112, and the stopper 180 is coupled to the outer end of the outlet
113 of the ladle body 110 to open and close the outlet 113.
[0034] The ladle body 110 has an outer shell 120, which forms the
outside wall thereof, and an insulator 130 having a multi-layer
structure inside the outer shell 120.
[0035] The outer shell 120 is made of a metal material, preferably
steel, which has sufficient strength and rigidity such that it can
maintain its structural shape against the weight and pressure of
molten aluminum contained inside the ladle, external impacts, and
the like while preventing the insulator 130 from being damaged.
[0036] The insulator 130 has a multi-layer structure in which an
outer molded refractory material 131 is attached to the inside wall
surface of the outer shell 120, and an outer castable refractory
132, an inner molded refractory 133, and an inner castable
refractory are stacked sequentially inside the outer molded
refractory 131.
[0037] The inner castable refractory 134 is a main refractory,
which is provided to be innermost and is in direct contact with
molten aluminum, contained inside the ladle body 110, in order to
prevent the heat of the molten aluminum from escaping to the
outside. The inner castable refractory 134 is made of a material
that is not chemically reactive with aluminum and is sufficiently
able to endure the weight of the molten aluminum contained
therein.
[0038] In addition, the inner castable refractory 134 has an inside
wall 134a protruding upward from the bottom central portion of the
ladle body 110. The inside wall 134a prevents heat from being
concentrated in the central portion of the ladle body 110 at an
early stage of the input of molten aluminum and prevents contained
molten aluminum from flowing, thereby delaying heat dissipation and
preventing the weight from being biased to one portion inside the
ladle body 110.
[0039] The inner molded refractory 133 serves as a refractory as
well as a buffer that alleviates weight and impact transferred
between the inner castable refractory 134 and the outer castable
refractory 132. The inner molded refractory 133 is made of a
silicon dioxide-based molded material, which has excellent
heat-insulating characteristics.
[0040] The outer castable refractory 132 has heat insulation and
durable properties, like the inner castable refractory 134, but is
made of a cheaper material than the inner castable refractory 134
for the sake of economic efficiency.
[0041] The outer molded refractory 131 serves as a refractory as
well as a buffer that alleviates weight and impact transferred
between the outer castable refractory 132 and the outer shell 120.
The outer molded refractory 131 is made of a silicon dioxide-based
molded material. For example, the outer molded refractory 131 is
preferably made of a molded fiberglass material.
[0042] Like the ladle body 110, the cover 140 has an outer shell
150 made of steel and a multi-layer structure arranged inside the
outer shell 150. The multi-layer structure includes an outer molded
refractory 161, an outer castable refractory 162, an inner molded
refractory 163, and an inner castable refractory 164, which are
stacked sequentially inside the outer shell 150.
[0043] The cover 140 has a thermometer mounted thereon, which
indicates the temperature of the molten aluminum, and cover clamps
193, which fix the cover 140 in a closed state to the ladle body
110, are provided on the edge of the cover 140.
[0044] The stopper 180 is fitted into the outlet 113 of the ladle
body 110 and is fixed in that state by a stopper clamp 195. The
stopper 180 has a refractory 183 mounted on the portion thereof,
which is fitted into the outlet 113, and a hook 185 provided on the
externally exposed portion thereof. The hook 185 is used to draw
out the stopper 180.
[0045] With the above-described structure, the high-heat-retention
ladle according to an exemplary embodiment of the invention can
maintain the temperature of the molten aluminum contained in the
storage space of the ladle body 110, thereby making unnecessary the
processes of making an aluminum ingot and melting the aluminum
ingot again.
[0046] That is, with the multi-layer insulation structure, in which
the outer molded refractory 131, 161, the outer castable refractory
132, 162, the inner molded refractory 133, 163, and the inner
castable refractory 134, 164 are stacked sequentially inside the
outer shell 120, 150, the ladle body 110 and the cover 140 can
efficiently prevent the heat of the molten aluminum from escaping
to the outside, thereby suppressing the temperature drop of the
molten aluminum at about 1.degree. C./min or less.
[0047] Therefore, assuming that the shipping temperature of the
molten aluminum is approximately 750.degree. C., it is possible to
supply aluminum in a molten state, such that it can be directly
cast into a product, to a remote casting plant that requires a
delivery time of about 2 hours.
[0048] Therefore, an aluminum material supplier can advantageously
reduce manpower and facilities costs and shorten the aluminum
supply cycle, thereby improving cost efficiency and productivity,
since the process of making an ingot for the purpose of delivery
after having melted aluminum is not necessary.
[0049] In addition, since the product casting plant does not need
the process of melting again the supplied aluminum ingot, it is
possible to reduce product-manufacturing costs, improve
productivity, and reduce materials costs and provide better working
environment to workers by preventing the loss of aluminum due to
oxidation during melting as well as the output of pollutants.
[0050] Meanwhile, the present invention is not limited to the
certain exemplary embodiment as described above. In particular, the
insulator mounted inside the ladle body 110 and the cover 140 can
be variously selected.
[0051] Another exemplary embodiment of the invention is shown in
FIGS. 6 to 8.
[0052] FIG. 6 is a front elevational cross-sectional view showing a
high-heat-retention ladle for carrying molten aluminum according to
another exemplary embodiment of the invention, FIG. 7 is a top plan
cross-sectional view of the ladle shown in FIG. 6, and FIG. 8 is a
detailed view of a stopper of the ladle shown in FIG. 6.
[0053] Referring to FIGS. 6 to 8, in the ladle for carrying molten
aluminum according to this exemplary embodiment of the invention,
like the foregoing embodiment, the cover 140 is coupled to the
upper portion of the ladle body 110, the stopper 180 is fitted into
the outlet 113 of the ladle body 110, and the ladle body 110 and
the cover 140 have a multi-layer insulation structure.
[0054] In this embodiment, a castable refractory structure, which
is not reactive with molten aluminum, is provided in the innermost
portion of the ladle body 110. The castable refractory structure
can include different types of castable refractories depending on
respective portions of the ladle body 110. That is, an HD board
type castable refractory 213 is provided on the side wall of the
ladle body 110, a castable refractory 215 (trade name VIOALC),
which includes silicon dioxide (SiO.sub.2) 31%, aluminum oxide
(Al.sub.2O.sub.3) 35%, and calcium oxide (CaO) 33%, is provided on
the side wall in the outlet side, and a castable refractory 214,
which is made of silicon nitride (Si.sub.3N.sub.4) coupled silicon
carbide (SiC), is provided on the bottom of the ladle body 110.
[0055] An outer molded refractory 211 is provided directly inside
of the steel outer shell 120, which forms the contour of the ladle
body 110. It is preferred that the outer molded refractory 211 be
made of a microporous insulator (trade name WDS), which includes
silicon dioxide (SiO.sub.2) 80% and silicon carbide (SiC) 15%.
[0056] An inner molded refractory 212 is provided between the
castable refractories 213, 214, and 215 and the outer molded
refractory 211. The inner molded refractory 212 can be made of
ceramic pelts to which inorganic binder is impregnated.
[0057] Likewise, the cover 140 is structured such that a molded
refractory 211 and a castable refractory 212 are provided inside
the outer shell 150.
[0058] The high-heat-retention ladle of this embodiment can reduce
its weight and thus improve delivery performance, since suitable
types of refractory layers, each of which has a suitable thickness,
are provided to satisfy a variety of insulating conditions
according to the respective portions of the ladle body.
[0059] The foregoing descriptions of specific exemplary embodiments
of the present invention have been presented for the purposes of
illustration and description. They are not intended to be
exhaustive or to limit the invention to the precise forms
disclosed, and obviously many modifications and variations are
possible in light of the above teachings. The exemplary embodiments
were chosen and described in order to explain certain principles of
the invention and their practical application, to thereby enable
others skilled in the art to make and utilize various exemplary
embodiments of the present invention, as well as various
alternatives and modifications thereof. It is intended that the
scope of the invention be defined by the Claims appended hereto and
their equivalents.
* * * * *